export { }
let fs = require('fs');
// 读文件每次读3个字节
let rs = fs.createReadStream('./1.txt', { highWaterMark: 3 });
// 
rs.on('data', function (data) {
    /**
     * 123
     * 456
     * 789
     */
    console.log(data,data.toString());
});
rs.on('end', function (data) {
    console.log('end');
});